Vibratory piano tuning apparatus



1965 J. G. ALLEN 31 33 VIBRATORY PIANO TUNING APPARATUS 7 Filed Oct. 15, 1963 i TUNING FORK /0 Joseph Guy Allen IN VEN TOR.

United States Patent 3 195,392 VIBRATORY PIANb TUNING APPARATUS Joseph Guy Alien, Box 376, Pinevilie, La. Filed Get. 15, 1963, Ser. No. 316,418 7 Claims. (Cl. 84457) This invention relates to a portable piano tuning apparatus embodying practical easy-to-use facilities through the medium of which a piano tuner, a technician, or a student can concentrate on, hear and accurately count vibratory beats and pitch frequencies, and while thus undisturbed, can expeditiously, but accurately, set the temperament of a piano which is being tuned.

The piano tuner, regardless of prevailing difficulties, sets out to tune the piano at hand so thatwhere practicabletbe overall pitch will conform to a desired standard; namely, A-natural at 440 international pitch. The fact that there are groups of two and three treble strings (except for single strings in the low register) poses a part of the overall tuning problem. However, with the aid of pitch pipes, preferably a full set of tuning forks, a reliably trained ear, enduring patience and skill of counting beats, as required, the average tuning job is generally well done. To do so, including the final step of setting the temperament, requires an expenditure of much and valuable time.

With the above very broad picture in mind, it is a general objective here to provide the piano tuner with a simple feasible instrument or apparatus which will enable him to ascertain when the pitch of each and every string is precisely correct. More particularly, the invention comprises a relatively small pitch testing, comparing and verifying apparatus which measures and confirms the pitch of each string. By striking and vibrating the particular string which is being tuned and tested with the usual key-controlled hammer, the moment the intended pitch of the string is attained the sound responsive means of the stated apparatus comes into play and, functioning as though it were a telltale signal, it alerts the user so that he can give the string the finishing touch and go on to the next ascending or descending string. Not only does the invention provide the desired audible signal, it concentrates and aguments it my amplification to a degree of focal intensity that with the aid of a stethoscope or the like a single tone, C-natural for example, an interval C to F, or a chord (LE-G, on the piano can thus be tested, compared and confirmed. Accordingly, a user who is uncertain of his ear training and beat-counting ability and skill can reliably achieve the desired tuning result. Then, too, this invention saves time in those frequently recurring instances where, because of slippage and strain, many of the strings have to be tuned again and again for accuracy.

Briefly, the apparatus comprises, in combination, at least one standard tuning fork, C-natural for example; means for supporting the fork in the vibrating telltale or pitch measuring position, said means embodying a hollow body defining an acoustical chamber; and a stethoscope or the like which is operatively and communicatively connected to said chamber.

In carrying out the invention a regular set of tuning forks is used. This is to say, thirteen such forks are employed ranging chromatically from middle C to C one octave above the same. These forks can be used one at a time, two at a time or three at a time, depending on whether the user desires to find the starting pitch of middle C, the pitch of an interval C (the tonic) and G (the dominant) or alternatively, a triple tone chord C-E-G, as the case may be. It follows that the fork support means is provided with three socket members, the main one at the center and the supplemental or auxiliary ones to the left and right thereof. The manner in 3,195,392 Patented July 20, 1965 which these forks are employed for best results will be set forth in detail in the body of the specification which follows.

Also, and as will be hereinafter set forth, the present invention has to do with a simple portable instrument or apparatus which is purely mechanical, manually usable and requires no electrical Or electronic equipment. For example, the tuning fork holding and supporting means comprises a self-standing acoustical hollow body. A simple hollow Wooden or equivalent box has been found to be adequate. This box can be placed atop the piano or on the shelf-like ledge proximal to the strings which are being tuned. The hollow of the box provides an acoustical chamber. The top of the box has three socket members embodied therein for the selectively usable attachable :and detachable tuning forks.

While an acceptable result is attainable by merely attaching the stethoscope to a front wall of the box, a more effective and reliable result is attained by incorporating a Victrola reproducer head or unit in the chamber of the box in such a manner that the needle contacts the aligned stem of the tuning fork. The fork vibrates the needle and the needle acts on and vibrates the cooperatively associated diaphragm. The tone discharge neck extends through an opening provided therefor in the front wall of the box to which the intake tube of the stethowhich:

FIGURE 1 is a view in perspective showing a fragmentary portion of a piano and showing, What is more significant, the portable piano tuning apparatus and a preferred manner in which it is usable;

FIGURE 2 is a view with parts in section and elevation and which is taken on an enlarged scale on the plane of the section line 2-2 of FIGURE 1 looking in the direction of the indicating arrows;

FIGURE 3 is a horizontal section on the section line 33 of FIGURE 2.

With reference first to FIG. 1 the piano which is to be tuned by the piano tuner or technician (as the case may be) is denoted by the numeral 6 and the conventional keyboard thereof is designated at 8. The two white keys which are significant, generally speaking, in both the explanation and understanding of the concept are designated by suitable legends middle C and international pitch A respectively.

The source of vibration could, within the purview of the present inventive concept, constitute responsive vibration means other than that illustrated in FIG. 1. It is desirable to point out at the outset that the herein disclosed invention is wholly mechanical in nature. To the ends desired the invention requires the use of standard precisely tuned tuning forks; namely, thirteen (13) chromatic tuning forks ranging from middle C to C an octave above it and singly and collectively used for finding and comparing and verifying single tones, intervals of two tones, and three harmonious tones productive of a prescribed chord, for example, a tonic chord C-E-G, or, the three forks selected for a different chord, the subdominant F-A-C. The trained and experienced piano tuner or technician, in addition to having a knowledge in respect to chromatic tuning forks, fundamentals in relation to single, double and triple tones is concerned with the basic components of a musical tone such as pitch, intensity, duration and amplitude. Although a single tuning fork is here shown :5 it is significant to point out that the overall invention involves the use of the aforementioned set of tuning forks (13 chromatically tuned forks). The one illustrated in FIG. 1 could, of course, be responsive to produce middle C but for convenience it is referred to here as responding to the frequency of international pitch A at 440. It is designated by the numeral and has the usual vibratory fingers or legs 12 and stem 14 which is fitted removably into a holding socket 16 provided therefor in the top wall 18 of the box-like amplifying case 20. This case or box comprises, as shown in FIG. 2, a bottom wall 22, back or rear wall 24 rising therefrom, vertical end walls 26 and a front wall 28. The front wall is provided with a suitable opening at the center thereof as at 30 which registers with a cooperating opening 32 in a disk-like plate 34 which is mounted or fastened on the front wall and which in practice may be ornamented with musical notations representing single notes, chords or the like (not shown). These interconnected walls are made of suitable materials and define a hollow chamber 36. The bottom portion of the socket 16 depends into and communicates with the chamber 36. This socket 16 is at the center of the top wall between a pair of auxiliary sockets 38 at the left and 40 at the right (FIG. 1) which are constructed to accommodate and support additional tuning forks (not detailed). These sockets are employed singly and collectively and the tuning forks 10 are employed selectively and can be used, one in the manner illustrated, or two or a group of three as desired.

It is a matter of common knowledge that when the stem of a tuning fork is simply held and supported atop or otherwise responsively placed on a resonating box with the latter positioned at the piano (FIG. 1) it will sympathetically respond if a string on the piano is struck and the pitch of that string corresponds to the pitch of the tuning fork. While sympathetic vibration could be resorted to in the use of the tuning fork in conjunction with the amplifying or resonating box 20, it is preferred to accomplishv the desired result by bumping and forcing the tuning fork into vibration before applying the stethoscope denoted generally at 42. This stethoscope comprises an intake tube 44 having an end 46 connected with a nipple or neck 48 protruding through the openings 30 and 32. as shown in FIG. 2, said nipple being a part of the tone arm 50 of an oldtime or well-known Victrolatype reproducer head 52. This head comprises a holder or pickup 54 having a vibratory mica diaphragm or the like 56 and an attached radial arm 58 with a socket 62 having a setscrew carrying a needle or stylus 64 which projects into the socket 16 and on which the bottom of the stem 14 of the tuning fork rests in the manner shown to transmit vibrations to the diaphragm. With further reference to the stethoscope the usual ear tubes 66 are provided and connected by branch means 68 to the end 70 of the tube 44. These tubes 66 terminate in suitable ear plugs or equivalent earpieces 72.

Experience has shown that a simple stethoscope 42 constitutes a highly satisfactory amplified sound wave pickup and hearing aid for the user.

In practice when teaching a student the art and skill 'of counting beats, this sensitive instrument or apparatus is placed atop the piano in the manner illustrated in FIG. 1. It is accordingly in a satisfactory position to amplify the particular string or strings on the piano which are intentionally set into vibration. The instructor selects a fork from the set, say the C-fork. He then proceeds to strike or bump it and then quickly places the stem in the socket 16 and tightens and tunes the string to near unison with the fork. At this stage the beats begin to form and become so distinct that the student should have no difiiculty in detecting and gauging them. Then when he tightens the selected string to the point that it is in perfect unison with the vibrations of the tuning fork, the beats fade out and disappear. Should he lower the string, say just a bit, t e beats reappear. Then,

too, if he continues to lower the string the beats become faster and by this method of raising and lowering the string while the tone of the tuning fork is being heard the student can by practice understand precisely what is meant by having the skill of counting beats. In fact, the student soon learns that there is a definite and distinct difference in a tone which is musical and when the beats are heard in waves.

If the invention is used for an instructing apparatus, when teaching the student how to set the beats in the temperament the instructor simply selects two tuning forks forming the first interval of the temperament. He bumps the forks and places them in the desired sockets say 38 or 40, as the case may be. Assuming that the student has learned by this time to detect beats he can readily tell how slow or fast the beats should be. As many as three forks can be placed in the sockets 16, 38 and 40 atop the resounding and resonating box for easy-to-hear amplification in the chamber 36. It follows that this invention is a highly satisfactory ways and means which enables a piano tuner, a student, or technician to achieve a highly reliable and satisfactory job which might not otherwise be attainable for the reasons set forth in the beginning of the specification.

The tuning fork in a vibrating position in its. intended socket atop the resonating box or chamber, plus the phonograph head pickup 52 and stethoscope in conjunction therewith serves to accomplish the end results desired.

There are, of course, certain so-called old pianos which tend to give trouble when the piano tuner attempts to set the same to standard pitch. Experience has shown that when the user is called upon to tune this type of a piano, especially in a room or building where reverberations and acoustical difiiculties are encountered it is quite possible to obtain fairly good results without using tuning forks v and simply placing the box or case 20 atop the piano and using it as a sound resonating box in conjunction with the stethoscope or equivalent means.

As previously suggested and since a tuning fork is sympathetically vibratory, placingthe fork in its socket in the manner shown in FIG. 1 without forced vibration (by bumping) it can be seen that when the string or strings which correspond with the selected fork are individually and selectively tuned to correct pitch, that is, when the pitch achieved corresponds with the fork, the fork will sympathetically vibrate and will function as a signal indicating that the pitch desired for a particular or given string has been reached. It will be seen, therefore, that the construction and use of the invention is such that it is versatile and consequently an innovation in that it aptly serves the purposes for which it is intended.

For best end results the lid or cover of the piano is removed. The portable piano tuning device (the boxlike case 20) is placed in position atop the piano approximately in line with the string which is being tuned. The tuning hammer is properly hooked on the pianos tuning pin in the position assumed when preparing to raise the pitch of the selected string. The tuning fork 10 is bumped (in any suitable manner) the stem thereof is placed in the socket 16, the correct piano key is depressed and the tuning hammer is pulled to draw the string so that the vibratory pitch is in unison with the pitch of the fork. This result can be accomplished in a few seconds. However, the piano tuner does not have'to hurry because the phonograph type reproducer head 52 in the chamber 36 of the box 20 is sealed substantially airtight and will actually prolong and hold the tone for about sixty seconds.

The gist of the information which has to do with how a piano student may use the apparatus involves the use of tWo of a set of 13 chromatic tuning forks. It is to be understood, of course, that the student has already learned what a beat is and that he is interested in learning to set the pianos temperament. The interval selected involves two tones; namely C and F. Normally, that is, without the present invention, when the student strikes the interval which he is attempting to listen to he would find it diificult here because (as is generally the case) of outside interference and bombarding noises. With the device 20 set in position atop the piano (with the cover or lid removed) the student simply selects the C and F forks, bumps and places them one in the socket 38 (PEG. 1) and the other one in the socket 40, the tuning fork having been removed. Under the circumstances and with this setup the student shuts out outside interference and the sound waves heard are distinct, as can be full well appreciated.

The foregoing is considered as illustrative only of the principles of the invention. Further, since numerous modifications and changes will readily occur to those skilled in the art, it is not desired to limit the invention to the exact construction and operation shown and described, and accordingly all suitable modifications and equivalents may be resorted to, falling within the scope of the invention as claimed.

What is claimed as new is as follows:

1. A pitch comparing and verifying apparatus comprising a portable hollow body the hollow portion of which provides a chamber, a conventional-type phonograph diaphragm-equipped reproducer head confined and supported in said chamber and equipped with a vibratory needle surrounded by a sleeve, said sleeve providing a socket member for reception and temporary retention of the stem of a tuning fork, said head having a sound discharging neck accessible for use through a wall of said body, and a standard tuning fork of a given vibrating pitch measuring frequency and in combination, the stem of said fork being fitted telescopically into the socket of said socket member and having positive engagement with and for exciting and vibrating said needle.

2. The apparatus according to claim 1, and in combination, a stethoscope embodying a sound input tube communicatively connected with the aforementioned neck.

3. In combination, a stethoscope embodying a single sound pickup tube communicatively connected with auxiliary ear tubes, and ear tubes terminating with earpieces, acoustical chamber means with which the intake end of said pickup tube is communicatively connected, and string pitch frequency measuring, comparing and verifying means comprising at least one standard tuning fork having the usual stem, and socket means carried by and accessible on said chamber means, the stem of said tuning fork being cooperatively and separably connected with said socket means.

4. String pitch testing and verifying means functionally designed and structurally adapted for use by a piano tuner, technician or an apprentice and student of frequency measurin and comparing needs comprising a portable hollow box-like body, the hollow portion of which constitutes an acoustical chamber, said body having a bottom wall which permits the body to be set firmly in a usable position atop a selected surface of the piano which is to be tuned and also having at top wall, said top wall being provided with a primary socket member openended with its inner open end opening into the aforementioned chamber, said socket member being adapted to removably receive the stem of a tuning fork, a conventional tuning fork having a stem seated removably in the socket of said socket member, said top wall being further provided to the left and right of said first-named socket member with auxiliary socket members projecting above the plane of the top wall and providing holders for stem portions of additional selectively usable tuning forks, and a stethoscope embodying a sound listening tube, said tube being communicatively connected at a sound wave intake end thereof with said body and communicating with said chamber.

5. The structure defined in claim 4 and in combination, a conventional type phonograph diaphragm-equipped reproducer head confined and supported in said chamber and equipped with a vibratory needle, said needle being oriented and aligned with and projecting into the socket portion of said primary socket member and being adapted to contact the aforementioned stem of said tuning fork, said reproducer head having a sound discharge neck with which the intake of said sound listening tube is communicatively connectible.

6. Pitch testing and verifying means for use by a piano 3 tuner, a technician or an apprentice piano tuner comprising: at least one standard tuning fork, and supporting and holding means for retaining said tuning fork in a readily attachable and detachable manner and freely vibrating position, said means functioning to conduct the audible sound waves emanating from the tuning fork when vibrating, whereby the user is thus enabled to test and compare the pitch of a vibrating string repeatedly and until the pitch of the string is precisely in unison with the established pitch of said tuning fork, said means embodying a hollow body whose hollow portion constitutes an acoustical chamber, said body being portable, self-standing and provided with auxiliary holders for additional tuning forks, whereby to permit the user to employ the tuning forks singly or collectively, and in combination, a stethoscope having a sound listening tube communicatively connected with said body and the acoustical chamber therein.

7. A string pitch testing, comparing and confirming apparatus comprising: a hollow box, the hollow portion of which constitutes an acoustical chamber, said box having a first wall which permits the box to be set firmly in a string pitch testing, comparing and verifying position atop a predetermined portion of the piano or supported in a corresponding manner adjacent the string whose pitch is being tuned and set, also having a second wall provided with a socket member, said socket member having a portion thereof opening into and communicating with said chamber, said socket member being constructed and oriented relative to the second wall and chamber to removably receive and accessibly position and retain the stem of a standard tuning fork, and a stethoscope embodying a sound pickup tube communicatively joined with a wall portion of said box and communicating with said chamber and, in combination, a standard tuning fork, a C-fork, for example, having a stem fitted into the socket of said socket member.

References Cited by the Examiner UNITED STATES PATENTS 906,608 12/08 Bryant 84-456 1,201,958 10/16 Halls et al. 181-32 1,328,838 1/20 Kirk 84-457 1,419,919 6/22 Deagan 84-457 2,152,177 3/39 Eisenbeis et al. 84-454 2,228,249 1/41 Alyn 84-454 2,390,237 12/45 Bryant 84-456 2,520,520 8/50 Woodard 84-457 X 2,779,920 1/57 Petrofr' 84-454 3,063,328 11/62 Greider 84-456 X LEO SMILOW, Primary Examiner. 

3. IN COMBINATION, A STETHOSCOPE EMBODYING A SINGLE SOUND PICKUP TUBE COMMUNICATIVELY CONNECTED WITH AUXILIARY EAR TUBES, AND EAR TUBES TERMINATING WITH EARPIECES, ACOUSTICAL CHAMBER MEANS WITH WHICH THE INTAKE END OF SAID PICKUP TUBE IS COMMUNICTIVELY CONNECTED, AND STRING PITCH FREQUENCY MEASURING, COMPARING AND VERIGYING MEANS COMPRISING AT LEAST ONE STANDARD TUNING FORK HAVING THE USUAL STEM, AND SOCKET MEANS CARRIED BY AND ACCESSIBLE ON SAID CHAMBER MEANS, THE STEM OF SAID TUNING FORK BEING COOPERATIVELY AND SEPARABLEY CONNECTED WITH SAID SOCKET MEANS. 